//独立按键按键1返回1，按键2返回2...否则返回0
#include <REGX52.H>
#include "Delay.h"

unsigned char dulianjian()
{
	char KeyNumber=0;
	
	if(P3_1==0){Delay(20);while(P3_1==0);Delay(20);return 1;}
	if(P3_0==0){Delay(20);while(P3_0==0);Delay(20);return 2;}
	if(P3_2==0){Delay(20);while(P3_2==0);Delay(20);return 3;}
	if(P3_3==0){Delay(20);while(P3_3==0);Delay(20);return 4;}
	
	return KeyNumber;
}